The swimming pool type nuclear reactors are well known and their uses for the purpose of producing heat have been widely proposed. IEEE Spectrum, February 1984 pp. 50-55 describes various proposals of the use of low temperature nuclear reactors for space heating. Most of the reactors described in the above article use closed circuit moderator-coolant flows which are pressurized throughout. The Canadian Slowpoke reactor which is also mentioned in the article is open circuited in that it has a pool of light water under atmospheric pressure as a part of the circuit.
The present inventor co-authored a paper presented at the technical committee meeting and workshop of International Atomic Energy Agency held at Krakow, Poland on Dec. 5-9. 1983. The paper describes the prototype 2MWt Slowpoke-3 heating reactor concept. The present inventor also presented an article "Nuclear electricity from a low-temperature organic Rankine cycle engine" at the 1984 Annual Conference of the Canadian Society for Mechanical Engineering, Halifax, Nova Scotia, May 23-25, 1984. It was proposed there that a pumped Slowpoke reactor results in a higher mean temperature supplied to the Rankine engine. An intermediate water loop is used in both circuits to avoid any Freon [Trademark] entering the reactor pool.
U.S. Pat. No. 3,308,032, Mar. 7, 1967 (Berthod) teaches swimming pool type reactors in which an independent cooling water circulation system is set up within the body of the swimming pool water to limit surface radioactivity from nitrogen 16. By the use of suitable guides and/or pressure distribution arrangements e.g. baffles etc in the pool, independent cooling water circulation system which includes a pump will ensure that the cooling water will flow according to a definite pattern in one direction or the other through the core and the body of the pool water. The patent fails to concern itself with increasing the mean temperature of the coolant-moderator or mention electricity generation with its associated problems.
U.S. Pat. No. 3,769,789, Nov. 6, 1973 (Niggermann) discloses a power conversion system employing a Rankine cycle engine wherein an organic fluid such as toluene is used as the working medium. The system uses gas combustion at a temperature of about 3000.degree. F. which heats the toluene to produce superheated vapour of about 700.degree. F. The superheated vapour drives a turbine to produce electricity.